Condensation is the change of water from its gaseous form (water vapor) into
liquid water. Condensation generally occurs in the atmosphere
when warm air rises, cools
and looses its capacity to hold water vapor. As a result,
excess water vapor condenses to form cloud droplets.
The upward motions that generate clouds can be produced by
convection in unstable air,
convergence associated
with cyclones,
lifting of air by fronts and lifting over elevated
topography such as mountains.